Change default to stop recording when muted (#206)

Author: hiroshihorie

api/audio/audio_device.h

@@ -181,6 +181,9 @@ class AudioDeviceModule : public webrtc::RefCountInterface {
   // not be present in the stats.
   virtual std::optional<Stats> GetStats() const { return std::nullopt; }
 
+  // Whether to stop recording when all streams are muted.
+  virtual bool IsStopOnMuteModeEnabled() const { return true; }
+
 // Only supported on iOS.
 #if defined(WEBRTC_IOS)
   virtual int GetPlayoutAudioParameters(AudioParameters* params) const = 0;

media/engine/webrtc_voice_engine.cc

@@ -1759,7 +1759,18 @@ bool WebRtcVoiceSendChannel::MuteStream(uint32_t ssrc, bool muted) {
       if (adm) {
         RTC_LOG(LS_INFO) << "WebRtcVoiceSendChannel::MuteStream: ADM:"
                          << is_all_muted;
-        adm->SetMicrophoneMute(is_all_muted);
+
+        if (adm->IsStopOnMuteModeEnabled()) {
+          if (!is_all_muted && !adm->Recording()) {
+            if (adm->InitRecording() == 0) {
+              adm->StartRecording();
+            }
+          } else if (is_all_muted && adm->Recording()) {
+            adm->StopRecording();
+          }
+        } else {
+          adm->SetMicrophoneMute(is_all_muted);
+        }
       }
     }
   }

modules/audio_device/audio_engine_device.h

@@ -372,6 +372,8 @@ class AudioEngineDevice : public AudioDeviceModule, public AudioSessionObserver
 
   int32_t InitAndStartRecording();
 
+  bool IsStopOnMuteModeEnabled() const override;
+
  private:
   struct EngineStateUpdate {
     EngineState prev;

modules/audio_device/audio_engine_device.mm

@@ -88,6 +88,10 @@
   engine_state_.voice_processing_bypassed = voice_processing_bypassed;
 }
 
+bool AudioEngineDevice::IsStopOnMuteModeEnabled() const {
+  return false;
+}
+
 AudioEngineDevice::~AudioEngineDevice() {
   RTC_DCHECK_RUN_ON(thread_);